Recently, with the rapid advance in IT (Information Technology) and the increased desire for communication, radio communication appliances, such as portable terminals and the like, have become necessities of modern people. However, as such radio communication appliances are increasingly used, the influence of electromagnetic waves generated from portable terminals on the human body is becoming an important issue. For example, the influence of electromagnetic waves on the human body in the frequency band of currently-used mobile phones has become an issue. Further, it has been reported that electromagnetic waves can influence various kinds of diseases such as leukemia, brain tumors, headaches, amblyopia, electroencephalogram abnormality occurring when electromagnetic waves accumulate in the human body, male reproductive function disorder, and the like.
Particularly, in Jun. 1, 2011, International Agency for Research on Cancer (IARC), which is a research institution affiliated with the World Health Organization (WHO), reported that the danger of causing brain cancer is increased when a mobile phone is used. The electromagnetic waves generated from mobile phone conversations are classified as a 2B-grade cancer-causing material, which is the third highest grade of cancer-causing material. Exhaust gas discharged from an automobile engine belongs to the 2B-grade cancer-causing material. WHO has announced the opinion that there is no indisputable evidence showing the correlation between the use of a mobile phone and the generation of cancer. However, such research reversed this opinion.
The WHO suggests the following guidelines: 1) children must not use a mobile phone if it is not urgent, 2) a mobile phone must not be placed near the human body, 3) a telephone must be used at the time of a long conversation, and 4) a letter message must be used if possible. However, mobile phones have become necessities for daily life, so it is obvious that persons requiring a lot of mobile phone conversation will be influenced by these guidelines.
Thus, in advanced countries, various efforts have been made to prevent users from being exposed to electromagnetic waves when using a mobile phone. For example, in England, mobile phones are sold together with the warning sentence “health is endangered by the excessive use of a mobile phone”.
Further, attempts have been made to develop electronic products for minimizing the generation rate of electromagnetic waves, and research into technologies for reducing the inevitably-generated electromagnetic waves has been continuously carried out.
Even in Korea, like advanced countries, there are standards regarding the specific absorption rate (SAR) of electromagnetic waves in the human body and these standards are enforced. Mobile phones can be sold in the market only when they comply with these standards. However, even in Korea, like the announcement of the WHO, the influence of electromagnetic waves generated from a mobile phone on the human body is continuously being issued, and these standards cannot completely alleviate the anxiety and worry of a normal person although they are provided and enforced.
All the electronic products carried or used by users generate electromagnetic waves, and, particularly, radio communication terminals, such as mobile phones and the like, which transmit and receive radio waves of a specific frequency using an antenna, generate a large amount of electromagnetic waves. Therefore, different research and various technologies for reducing electromagnetic waves to allow the electromagnetic waves not to have an influence on the human body have been conducted, but no particular plan has been formulated.
Therefore, it is required to develop methods of reducing the influence of electromagnetic waves on the human body even when a mobile phone complies with the standards.